"BUILDING & CONSTRUCTION MYANMAR" OCT 30 - NOV 1,2014

ventilation fan centrifugal fan industrial fan

ventilation fan Ventilation is the intentional introduction of outside air into a space.[1] Ventilation is mainly used to control indoor air quality by diluting and displacing indoor pollutants; it can also be used for purposes of thermal comfort or dehumidification when the introduction of outside air will help to achieve desired indoor psychrometric conditions. The intentional introduction of outside air can be categorized as either mechanical ventilation, or natural ventilation.[2] Mechanical ventilation uses fans to drive the flow of outside air into a building. This may be accomplished by pressurization (in the case of positively pressurized buildings), or by depressurization (in the case of exhaust ventilation systems). Many mechanically ventilated buildings use a combination of both, with the ventilation being integrated into the HVAC system. Natural ventilation is the intentional passive flow of outside air into a building through planned openings (such as louvers, doors, and windows). Natural ventilation does not require mechanical systems to move outside air, it relies entirely on passive physical phenomena, such as wind pressure, or the stack effect. Mixed mode ventilation systems use both mechanical and natural processes. The mechanical and natural components may be used in conjunction with each other or separately at different times of day or season of the year.[3] Since the natural component can be affected by unpredictable environmental conditions it may not always provide an appropriate amount of ventilation. In this case, mechanical systems may be used to supplement or to regulate the naturally driven flow. Outdoor air can also enter a building by infiltration - the uncontrolled flow of air from outdoors to indoors through leaks (unplanned openings) in a building envelope. In buildings that make no intentional design for mechanical or natural ventilation, circumstantial infiltration has been referred to as adventitious ventilation.[4] In exhaust ventilated buildings, the intended flow of outside air may enter through planned inlets, but it will also enter through unplanned leaks in the building envelope. Generally, all outside air that crosses the building envelope through leaks is referred to as infiltration, whether it is driven by mechanical systems or natural mechanisms like wind. In many instances, ventilation for indoor air quality is simultaneously beneficial for the control of thermal comfort. At these times, it can be useful to increase the rate of ventilation beyond the minimum required for indoor air quality. Two examples include air-side economizer strategies and ventilation pre-cooling. In other instances, ventilation for indoor air quality contributes to the need for - and energy use by - mechanical heating and cooling equipment. It hot and humid climates dehumidification of ventilation air can be a particularly energy intensive process. In many scenarios, heat recovery ventilation can reduce energy use for heating and cooling by facilitating sensible heat exchange between exhaust air and incoming ventilation air. Energy recovery ventilation transfers moisture in addition to sensible heat. However, heat recovery can increase the fan power required for ventilation, and may increase energy use for heating and cooling for periods when ventilation would be beneficial for the control of indoor thermal comfort.[5] The design of buildings that promote occupant health and well being requires clear understanding of the ways that ventilation airflow interacts with, dilutes, displaces or introduces pollutants within the occupied space. Although ventilation is an integral component to maintaining good indoor air quality, it may not be satisfactory alone.[6] In scenarios where outdoor pollution would deteriorate indoor air quality, other treatment devices such as filtration may also be necessary. In kitchen ventilation systems, or for laboratory fume hoods, the design of effective effluent capture can be more important than the bulk amount of ventilation in a space. More generally, the way that an air distribution system causes ventilation to flow into and out of a space impacts the ability for a particular ventilation rate to remove internally generated pollutants. The ability for a system to remove pollution is described as its "ventilation effectiveness". However, the overall impacts of ventilation on indoor air quality can depend on more complex factors such as the sources of pollution, and the ways that activities and airflow interact to affect occupant exposure. Ventilation should not be confused with air motion induced by ceiling fans or other devices. Air motion influences thermal comfort, it can decrease thermal stratification, and it may cause pollutant dilution by way of mixing, but it does not introduce outside air and therefore does not classify as ventilation. Ventilation should be considered for its relationship to "venting" for appliances and combustion equipment such as water heaters, furnaces, boilers, and wood stoves. Most importantly, the design of building ventilation must be careful to avoid the backdraft of combustion products from "naturally vented" appliances into the occupied space. This issue is of greater importance in new buildings with more air tight envelopes. To avoid the hazard, many modern combustion appliances utilize "direct venting" which draws combustion air directly from outdoors, instead of from the indoor environment. industrial fan Industrial fans and blowers are machines whose primary function is to provide a large flow of air or gas to various processes of many industries. This is achieved by rotating a number of blades, connected to a hub and shaft, and driven by a motor or turbine. The flow rates of these fans range from approximately 200 to 2,000,000 cubic feet (5.7 to 57000 cubic meters) per minute. A blower is another name for a fan that operates where the resistance to the flow is primarily on the downstream side of the fan. Functions and industries[edit] There are many uses for the continuous flow of air or gas that industrial fans generate, including combustion, ventilation, aeration, particulate transport, exhaust, cooling, air-cleaning, and drying, to name a few. The industries served include electrical power production, pollution control, metal manufacturing and processing, cement production, mining, petrochemical, food processing, cryogenics, and clean rooms. Centrifugal fans and axial fans Most industrial fans may be categorized into one of two general types: centrifugal fans and axial fans. Centrifugal For more details on this topic, see Centrifugal fan. The centrifugal design uses the centrifugal force generated by a rotating disk, with blades mounted at right angles to the disk, to impart movement to the air or gas and increase its pressure. The assembly of the hub, disk and blades is known as the fan wheel, and often includes other components with aerodynamic or structural functions. The centrifugal fan wheel is typically contained within a scroll-shaped fan housing, resembling the shell of the nautilus sea creature with a central hole. The air or gas inside the spinning fan is thrown off the outside of the wheel, to an outlet at the housing's largest diameter. This simultaneously draws more air or gas into the wheel through the central hole [2]. Inlet and outlet ducting are often attached to the fan's housing, to supply and/or exhaust the air or gas to the industry's requirements. There are many varieties of centrifugal fans, which may have fan wheels that range from less than a foot (0.3 meters) to over 16 feet (5 m) in diameter. Axial For more details on this topic, see Axial fan. The axial design uses axial forces to achieve the movement of the air or gas, spinning a central hub with blades extending radially from its outer diameter. The fluid is moved parallel to the fan wheel's shaft, or axis of rotation. The axial fan wheel is often contained within a short section of cylindrical ductwork, to which inlet and outlet ducting can be connected. Axial fan types have fan wheels with diameters that usually range from less than a foot (0.3 meters) to over 30 feet (9 m), although axial cooling tower fan wheels may exceed 82 feet (25 m) in diameter.[1] In general, axial fans are used where the principal requirement is for a large volume of flow, and the centrifugal design where both flow and higher pressures are required. Design paths There are several paths to determining a fan design for an application. For industries where the application requirements do not vary greatly and applicable fan designs have diameters of around 4 feet (1.2 meters) or less, a standard or pre-engineered design might be selected. When the application involves more complex specifications or a larger fan, then a design based on an existing model configuration will often satisfy the requirements. Many model configurations already cover the range of current industry processes. An appropriate model from the fan company's catalogue is selected, and the company's engineers apply design rules to calculate the dimensions and select options and material for the desired performance, strength and operating environment. Some applications require a dedicated, custom configuration for a fan design to satisfy all specifications. All industrial fan designs must be accurately engineered to meet performance specifications while maintaining structural integrity. For each application, there are specific flow and pressure requirements. Depending on the application, the fan may be subject to high rotating speeds, an operating environment with corrosive chemicals or abrasive air streams, and extreme temperatures. Larger fans and higher speeds produce greater forces on the rotating structures; for safety and reliability, the design must eliminate excessive stresses and excitable resonant frequencies. Computer modeling programs for computational fluid dynamics (CFD) and finite element analysis (FEA) are often employed in the design process, in addition to laboratory scale model testing. Even after the fan is built the verification might continue, using fan performance testing for flow and pressure, strain gage testing for stresses and tests to record the fan's resonant frequencies. Fan subtypes Fan types and their subtypes are industry standard, recognized by all major fan producers. Centrifugal Any of these fan subtypes can be built with long-lasting erosion-resistant liners. Airfoil (Air foil) – Used for a wide range of applications in many industries, fans with hollow, airfoil-profiled blades are designed for use in airstreams where high efficiency and quiet operation are required. They are used extensively for continuous service at ambient and elevated temperatures in forced and induced draft applications in the metals, chemical, power generation, paper, rock products, glass, resource recovery, incineration and other industries throughout the world. Backward curve – These fans have efficiencies nearly as high as the airfoil design. An advantage is that their single-thickness, curved plate blades prevent the possibility of dust particle buildup inside the blade, as may occur with perforated airfoil blades. The robust design allows high tip-speed operation, and therefore this fan is often used in high-pressure applications. Backward inclined – These fans have simple flat blades, backwardly inclined to match the velocity pattern of the air passing through the fan wheel for high-efficiency operation. These fans are typically used in high-volume, relatively low-pressure, clean air applications. Radial blade – The flat blades of this type are arranged in a radial pattern. These rugged fans offer high pressure capability with average efficiency. They are often fitted with erosion-resistant liners to extend rotor life. The housing design is compact to minimize the floor space requirement. Radial tipped – These fans have wheels that are backward curved, but in a way slightly different from backward curved fans. Backward curved fans' have wheels whose blades curve outward, while radial-tip fans' blades are curved inward and radial at their tips (hence the name "radial tip"), while still in a backwardly-curved configuration. Their curvature can also be thought of as radial at the tips but gradually sloping toward the direction of rotation. This rugged design is used in high-volume flow rate applications when the pressure requirement is rather high and erosion resistance is necessary. It offers medium efficiencies. A common application is the dirty side of a baghouse or precipitator. The design is more compact than airfoil, backward curved or backward inclined fans. Paddle-wheel – This is an open impeller design without shrouds. Although the efficiency is not high, this fan is well suited for applications with extremely high dust loading. It can be offered with field-replaceable blade liners from ceramic tiles or tungsten carbide. This fan may also be used in high-temperature applications. Forward-curve – This "squirrel cage" impeller generates the highest volume flow rate (for a given tip speed) of all the centrifugal fans. Therefore, it often has the advantage of offering the smallest physical package available for a given application. This type of fan is commonly used in high-temperature furnaces. However, these fans can only be used for conveying air with low dust loading because they are the most sensitive to particle build-up, but also due to the large number of blades that forward-curve wheels require. Industrial exhausters – This is a relatively inexpensive, medium-duty, steeply inclined flat-bladed fan for exhausting gases, conveying chips, etc. Pre-engineered fans (PE) – A series of fans of varying blade shapes that are usually available in only standard sizes. Because they are pre-engineered these fans may be available with relatively short delivery times. Often, pre-engineered rotors with various blade shapes may be installed into a common housing. These are often available in a wide range of volume and pressure requirements to meet the needs of many applications. Pressure blowers – These are high-pressure, low-volume blowers used in combustion air applications in furnaces or to provide “blow-off” air for clearing and/or drying applications. Surgeless blowers – These high-pressure, low-volume blowers have a reduced tendency for “surging” (periodic variation of flow rate) even at severely reduced fan speeds. This allows extreme turndown (low-flow) without significant pulsation. Mechanical vapor recovery blowers -These specially designed centrifugal fans are designed to increase temperature and pressure of saturated steam in a closed-loop system. Acid gas blowers - These veryheavy construction blowers are suitable for inlet pressures from full vacuum to 100 psig. Materials are selected for corrosion resistance to the gases and particulate handled. Specialty process gas blowers - These blowers are for high pressure petrochemical processes. Axial High-temperature axial fans – These are high-volume fans designed to operate against low flow resistance in industrial convection furnaces. They may be of either single-direction or bi-directional designs. Extremely rugged, they are most often used in high-temperature furnace (up to 1800 degF) applications. Tube axial fans – These are axial fan units with fan wheels located in cylindrical tubes, without inlet or outlet dampers. Vaneaxial fans – These axial flow fans have a higher pressure capability due to the presence of static vanes. Variable pitch axial fans – The blades on these axial fans are manually adjustable to permit the blade angle to be changed. This allows operation over a much wider range of volume/pressure relationships. The blades are adjusted periodically to optimize efficiency by matching the blade pitch to the varying conditions for the application. These fans are often used in mining applications. Variable pitch on-the-fly axial fans – These are similar to “Variable Pitch Axial Fans” except they include an internal mechanism that allows the blade pitch to be adjusted while the fan rotor is in motion. These versatile fans offer high-efficiency operation at many different points of operation. This instantaneous blade adjustment capability is an advantage that is possible with axial fans only. Cooling fans - (also referred to as "cooling tower fans") - These are axial fans, typically with large diameters, for low pressures and large volumes of airflow. Applications are in wet mechanical cooling towers, air-cooled steam condensers, air-cooled heat exchangers, radiators, or similar air-cooled applications. Mixed-flow fans - The gas flow patterns these fans produce resemble a combination of axial and centrifugal patterns, although the fan wheels often appear similar to centrifugal wheels. There are various types of mixed-flow fans, including gas-tight high-pressure fans and blowers. Flow control There are several means of controlling the flow rate of a fan, e.g., temporarily reducing the air or gas flow rate; these can be applied to both centrifugal and axial fans. Speed Variation - All of the fan types described above can be used in conjunction with a variable speed driver. This might be an adjustable frequency AC controller, a DC motor and drive, a steam turbine driver, or a hydraulic variable speed drive unit ("fluid drive"). Flow control by means of variable speed is typically smoother and more efficient than by means of damper control. Significant power savings (with reduced cost of operation) are possible if variable speed fan drives are used for applications that require reduced flow operation for a significant portion of the system operating life. Industrial Dampers - These devices also allow fan volumetric flow control during operation, by means of panels so as to direct gas flow or restrict the inlet or outlet areas. There is a variety of dampers available: Louvered Inlet Box Dampers Radial Inlet Dampers Variable Inlet Vane (VIV) Dampers Vortex Dampers Discharge Dampers

centrifugal fan Two kinds of the main blower (one axial blower) of one kinds. Machine to export the air by the rotation of the impeller in the circumferential direction by a centrifugal force from inside the impeller. There are two types of fans and blowers, e is the pressure orders 400㎜ ~ 350 or less, the pressure of the latter is higher. Hugok type, type songs on the shape of the wing, there is a distinction between such straight airfoil. In addition there are also various kinds of supporting methods and method of driving the impeller.By rotating it by a multiple-stage blade impeller in thin air is sucked and discharged at a right angle turn in the direction moyeojyeo the exhaust passage flows in the circumferential direction from both sides of the impeller. There are many uses for the continuous flow of air or gas that industrial fans generate, including combustion, ventilation, aeration, particulate transport, exhaust, cooling, air-cleaning, and drying, to name a few. The industries served include electrical power production, pollution control, metal manufacturing and processing, cement production, mining, petrochemical, food processing, cryogenics, and clean rooms. Multi Centrifugal Fans, Mini Centrifugal Fans, Small Centrifugal Fans/TFB-Series, Large Centrifugal Fans/TFB-G31 TFB-G36, Cabinet Centrifugal Fans/TFS-Series, Double Inlet Centrifugal Fans/TFB-GD Series, Filter Box (FANDORA)/Accessory Compact centrifugal fans for multi purpose. Low sound levels. Optimum design for high static pressure, high air volume and low power consumption. Enhance construct ability for easy installation, inspection and maintenance. Realize optimum ventilation systems for small spaces. Motor structure design for long life span of the motor. Exhaust the air from different places at once. Low sound levels.Easy installation.Easy to check and repair by removing the motor and the fan.The appearance of quadrilateral improved efficiency of installation at the desired location.Allowable temperature range: -10℃~+50℃ (It is even operable up to 90% of relative humidity under the room temperature.) Fanzic Cabinet Centrifugal Fans An extractor fan offers a relatively constant air volume even when the duct resistance(static pressure) is changed Efficient and noiseless in a region of high static pressure.Can be used between spiral ducts like inline fans.

duct fan A kind of turbo-jet. Format through the duct of the outer circumference (外 周) engine the air part of the compressor installing the fan for driving a separate turbine to form (by-pass jet) and the outer duct for guided to the jet nozzle to increase the injection quantity of gas (thrust increasing device) there are two types of. And through the outer periphery of the air duct part of the engine to drive the fan compressor installed in a separate turbine to form the outer duct to the jet nozzle to induce that the two types of a type that increases the amount of gas injected. Small diameter (小 口徑) which will include integrating the sirocco fan is attached to the blower inlet and which can be connected directly to a circular duct in the ceiling of the small axial flow (軸流) and indoor blower is inserted inside the duct belongs here. A general term for a compact-type blower with a rotary shaft of the axial center of the duct and blower can be matched and inserted between the ducts. axial fan That was installed on the wings of the steel sheet or cast aluminum material 4-12 sheets in the radial direction with respect to the axis, and flowing the gas in the axial direction by shaft rotation, as compared to other blower and suitable for high speed operation, it may be directly connected with the motor conduit It can be easily installed in the middle. Low wind pressure, has been used with a suitable blower or the like to the large-capacity ventilation, ventilation, ventilation of the press-in flue gas, the boiler. A device to install the rotary blades in the cylinder to send the gas in a direction parallel to the axis of rotation. The cooling fan of the engine that will be representative. Duct In-Line Fans is Hydrodynamics design for high efficiency.Stable shift of static pressure according to the change of airflow.Low sound level by applying acoustic material inside of the casing.Enhance construct ability (light, compact) and easy to connect the ducts.Low electric consumption by applying high efficient motor. Use to supply and exhaust the air of machinery room, generator space and electric facility space.Air controlling systems for the construction and smoke extraction system.Air conditioning of parking lot. See more at http://en.fanzic.com/products/details/duct-line-fans/#.VsaDmDrDvbwpletely closed-in motor. Ventilation through ducts of a tunnel building, factory, and so forth.Cooling and drying of an apparatus.Ventilation at a barn, facility warming house, etc. See more at http://en.fanzic.com/products/details/tfd-series-vane-axial-fans/#.VsaDqzrDvbw Large vane axial fans is Designed for large air volume and Low sound levels. Cooling for hot coil and ventilating the steam. See more at http://en.fanzic.com/products/details/large-vane-axial-fans/#.VsaDZjrDvbw Steel mill, shipbuilding yard, heavy industrial.Cooling and drying of an apparatus.Mixed Flow fans/TFJ-Series is The turbo axial blade based upon the hydrodynamics offers you less noise.The fixed air guide blade can move the air accurately and smoothly.Easy to install in a duct since there are the fixed legs at the center of the body.Attached the anti-vibration rubber in the fixed legs to be quiet. Ventilation ducts of buildings, mansions, hotels and hospitals.Intake and exhaust of the air of a factory, warehouse, etc. See more at http://en.fanzic.com/products/details/tfj-series-mixed-flow-fans/#.VsaDRTrDvbw industrial fan Industrial fans and blowers are machines whose primary function is to provide a large flow of air or gas to various processes of many industries. This is achieved by rotating a number of blades, connected to a hub and shaft, and driven by a motor or turbine. The flow rates of these fans range from approximately 200 to 2,000,000 cubic feet (5.7 to 57000 cubic meters) per minute. A blower is another name for a fan that operates where the resistance to the flow is primarily on the downstream side of the fan. There are many uses for the continuous flow of air or gas that industrial fans generate, including combustion, ventilation, aeration, particulate transport, exhaust, cooling, air-cleaning, and drying, to name a few. The industries served include electrical power production, pollution control, metal manufacturing and processing, cement production, mining, petrochemical, food processing, cryogenics, and clean rooms. Centrifugal For more details on this topic, see Centrifugal fan. The centrifugal design uses the centrifugal force generated by a rotating disk, with blades mounted at right angles to the disk, to impart movement to the air or gas and increase its pressure. The assembly of the hub, disk and blades is known as the fan wheel, and often includes other components with aerodynamic or structural functions. The centrifugal fan wheel is typically contained within a scroll-shaped fan housing, resembling the shell of the nautilus sea creature with a central hole. The air or gas inside the spinning fan is thrown off the outside of the wheel, to an outlet at the housing's largest diameter. This simultaneously draws more air or gas into the wheel through the central hole [2]. Inlet and outlet ducting are often attached to the fan's housing, to supply and/or exhaust the air or gas to the industry's requirements. There are many varieties of centrifugal fans, which may have fan wheels that range from less than a foot (0.3 meters) to over 16 feet (5 m) in diameter. Axial For more details on this topic, see Axial fan. The axial design uses axial forces to achieve the movement of the air or gas, spinning a central hub with blades extending radially from its outer diameter. The fluid is moved parallel to the fan wheel's shaft, or axis of rotation. The axial fan wheel is often contained within a short section of cylindrical ductwork, to which inlet and outlet ducting can be connected. Axial fan types have fan wheels with diameters that usually range from less than a foot (0.3 meters) to over 30 feet (9 m), although axial cooling tower fan wheels may exceed 82 feet (25 m) in diameter.[1] In general, axial fans are used where the principal requirement is for a large volume of flow, and the centrifugal design where both flow and higher pressures are required. There are several paths to determining a fan design for an application. For industries where the application requirements do not vary greatly and applicable fan designs have diameters of around 4 feet (1.2 meters) or less, a standard or pre-engineered design might be selected. When the application involves more complex specifications or a larger fan, then a design based on an existing model configuration will often satisfy the requirements. Many model configurations already cover the range of current industry processes. An appropriate model from the fan company's catalogue is selected, and the company's engineers apply design rules to calculate the dimensions and select options and material for the desired performance, strength and operating environment. Some applications require a dedicated, custom configuration for a fan design to satisfy all specifications. All industrial fan designs must be accurately engineered to meet performance specifications while maintaining structural integrity. For each application, there are specific flow and pressure requirements. Depending on the application, the fan may be subject to high rotating speeds, an operating environment with corrosive chemicals or abrasive air streams, and extreme temperatures. Larger fans and higher speeds produce greater forces on the rotating structures; for safety and reliability, the design must eliminate excessive stresses and excitable resonant frequencies. Computer modeling programs for computational fluid dynamics (CFD) and finite element analysis (FEA) are often employed in the design process, in addition to laboratory scale model testing. Even after the fan is built the verification might continue, using fan performance testing for flow and pressure, strain gage testing for stresses and tests to record the fan's resonant frequencies. Centrifugal Any of these fan subtypes can be built with long-lasting erosion-resistant liners. Airfoil (Air foil) – Used for a wide range of applications in many industries, fans with hollow, airfoil-profiled blades are designed for use in airstreams where high efficiency and quiet operation are required. They are used extensively for continuous service at ambient and elevated temperatures in forced and induced draft applications in the metals, chemical, power generation, paper, rock products, glass, resource recovery, incineration and other industries throughout the world. Backward curve – These fans have efficiencies nearly as high as the airfoil design. An advantage is that their single-thickness, curved plate blades prevent the possibility of dust particle buildup inside the blade, as may occur with perforated airfoil blades. The robust design allows high tip-speed operation, and therefore this fan is often used in high-pressure applications. Backward inclined – These fans have simple flat blades, backwardly inclined to match the velocity pattern of the air passing through the fan wheel for high-efficiency operation. These fans are typically used in high-volume, relatively low-pressure, clean air applications. Radial blade – The flat blades of this type are arranged in a radial pattern. These rugged fans offer high pressure capability with average efficiency. They are often fitted with erosion-resistant liners to extend rotor life. The housing design is compact to minimize the floor space requirement. Radial tipped – These fans have wheels that are backward curved, but in a way slightly different from backward curved fans. Backward curved fans' have wheels whose blades curve outward, while radial-tip fans' blades are curved inward and radial at their tips (hence the name "radial tip"), while still in a backwardly-curved configuration. Their curvature can also be thought of as radial at the tips but gradually sloping toward the direction of rotation. This rugged design is used in high-volume flow rate applications when the pressure requirement is rather high and erosion resistance is necessary. It offers medium efficiencies. A common application is the dirty side of a baghouse or precipitator. The design is more compact than airfoil, backward curved or backward inclined fans. Paddle-wheel – This is an open impeller design without shrouds. Although the efficiency is not high, this fan is well suited for applications with extremely high dust loading. It can be offered with field-replaceable blade liners from ceramic tiles or tungsten carbide. This fan may also be used in high-temperature applications. Forward-curve – This "squirrel cage" impeller generates the highest volume flow rate (for a given tip speed) of all the centrifugal fans. Therefore, it often has the advantage of offering the smallest physical package available for a given application. This type of fan is commonly used in high-temperature furnaces. However, these fans can only be used for conveying air with low dust loading because they are the most sensitive to particle build-up, but also due to the large number of blades that forward-curve wheels require. Industrial exhausters – This is a relatively inexpensive, medium-duty, steeply inclined flat-bladed fan for exhausting gases, conveying chips, etc. Pre-engineered fans (PE) – A series of fans of varying blade shapes that are usually available in only standard sizes. Because they are pre-engineered these fans may be available with relatively short delivery times. Often, pre-engineered rotors with various blade shapes may be installed into a common housing. These are often available in a wide range of volume and pressure requirements to meet the needs of many applications. Pressure blowers – These are high-pressure, low-volume blowers used in combustion air applications in furnaces or to provide “blow-off” air for clearing and/or drying applications. Surgeless blowers – These high-pressure, low-volume blowers have a reduced tendency for “surging” (periodic variation of flow rate) even at severely reduced fan speeds. This allows extreme turndown (low-flow) without significant pulsation. Mechanical vapor recovery blowers -These specially designed centrifugal fans are designed to increase temperature and pressure of saturated steam in a closed-loop system. Acid gas blowers - These veryheavy construction blowers are suitable for inlet pressures from full vacuum to 100 psig. Materials are selected for corrosion resistance to the gases and particulate handled. Specialty process gas blowers - These blowers are for high pressure petrochemical processes. Axial High-temperature axial fans – These are high-volume fans designed to operate against low flow resistance in industrial convection furnaces. They may be of either single-direction or bi-directional designs. Extremely rugged, they are most often used in high-temperature furnace (up to 1800 degF) applications. Tube axial fans – These are axial fan units with fan wheels located in cylindrical tubes, without inlet or outlet dampers. Vaneaxial fans – These axial flow fans have a higher pressure capability due to the presence of static vanes. Variable pitch axial fans – The blades on these axial fans are manually adjustable to permit the blade angle to be changed. This allows operation over a much wider range of volume/pressure relationships. The blades are adjusted periodically to optimize efficiency by matching the blade pitch to the varying conditions for the application. These fans are often used in mining applications. Variable pitch on-the-fly axial fans – These are similar to “Variable Pitch Axial Fans” except they include an internal mechanism that allows the blade pitch to be adjusted while the fan rotor is in motion. These versatile fans offer high-efficiency operation at many different points of operation. This instantaneous blade adjustment capability is an advantage that is possible with axial fans only. Cooling fans - (also referred to as "cooling tower fans") - These are axial fans, typically with large diameters, for low pressures and large volumes of airflow. Applications are in wet mechanical cooling towers, air-cooled steam condensers, air-cooled heat exchangers, radiators, or similar air-cooled applications. Mixed-flow fans - The gas flow patterns these fans produce resemble a combination of axial and centrifugal patterns, although the fan wheels often appear similar to centrifugal wheels. There are various types of mixed-flow fans, including gas-tight high-pressure fans and blowers. Flow control There are several means of controlling the flow rate of a fan, e.g., temporarily reducing the air or gas flow rate; these can be applied to both centrifugal and axial fans. Speed Variation - All of the fan types described above can be used in conjunction with a variable speed driver. This might be an adjustable frequency AC controller, a DC motor and drive, a steam turbine driver, or a hydraulic variable speed drive unit ("fluid drive"). Flow control by means of variable speed is typically smoother and more efficient than by means of damper control. Significant power savings (with reduced cost of operation) are possible if variable speed fan drives are used for applications that require reduced flow operation for a significant portion of the system operating life. Industrial Dampers - These devices also allow fan volumetric flow control during operation, by means of panels so as to direct gas flow or restrict the inlet or outlet areas. There is a variety of dampers available: Louvered Inlet Box Dampers Radial Inlet Dampers Variable Inlet Vane (VIV) Dampers Vortex Dampers Discharge Dampers See also Fan (mechanical) Axial fan design Specific fan power Three-dimensional losses and correlation in turbomachinery References Air Movement and Control Association". AMCA. Retrieved External links[edit] Air Movement and Control Association (AMCA) Online-calculation of axial flow fans: Free basic fan design tool for the calculation of axial flow fan geometry and power curves, cpu-cooling, industry fans, detailed result package available for download

FANZIC has been providing qualified industrial ventilation fans and blowers to customers throughout the world in 1987. After taking over LG Industrial Fan Division on 1998, we guarantee to satisfy requirements of the customer on the basis of rich experience and technical development in the meantime. FANZIC is a well-organized manufacturer and exporter which specializes in supplying Fans & Blowers. We have been providing quality fans and blowers to customers throughout the world in 1987. After taking over LG Industrial Fan Division on 1998, we guarantee to satisfy requirements of the customer on the basis of rich experience and technical development in the meantime. To meet world standard, under ISO 9001, we are thoroughly monitoring every single manufacture process which is design, quality control, marketing, purchasing, manufacture, and customer service.We provide a competitive price and high quality products to meet our customer's requirements in time. Therefore, we have a good reputation from our customers. Currently, our Products are used all over China, South-east Asia and Middle-east territories.We will do our best to keep our good reputation for product development, world best customer service, and best quality control. Our products include ventilation fan, industrial fan, centrifugal fan, duct fan, axial fan, industrial ventilating fan, ventilating fan and so on.